An in vivo genetic reversion highlights the crucial role of Myb-Like, SWIRM, and MPN domains 1 (MYSM1) in human hematopoiesis and lymphocyte differentiation.
Le Guen T, Touzot F, André-Schmutz I, Lagresle-Peyrou C, France B, Kermasson L, Lambert N, Picard C, Nitschke P, Carpentier W, Bole-Feysot C, Lim A, Cavazzana M, Callebaut I, Soulier J, Jabado N, Fischer A, de Villartay JP, Revy P.
Source : J Allergy Clin Immunol
2015 Dec 1
Pmid : 26220525
OBJECTIVES: We sought to characterize the underlying genetic cause of this syndrome.
METHODS: We performed genome-wide homozygosity mapping, followed by whole-exome sequencing.
RESULTS: Genetic analysis revealed that this novel disorder is caused by a homozygous MYSM1 missense mutation affecting the catalytic site within the deubiquitinase JAB1/MPN/Mov34 (JAMM)/MPN domain. Remarkably, during the course of our study, the patient recovered a normal immunohematologic phenotype. Genetic analysis indicated that this improvement originated from a spontaneous genetic reversion of the MYSM1 mutation in a hematopoietic stem cell.
CONCLUSIONS: We here define a novel human immunodeficiency and provide evidence that MYSM1 is essential for proper immunohematopoietic development in human subjects. In addition, we describe one of the few examples of spontaneous in vivo genetic cure of a human immunodeficiency.